|Publication number||US8047233 B2|
|Application number||US 11/939,680|
|Publication date||Nov 1, 2011|
|Filing date||Nov 14, 2007|
|Priority date||Nov 14, 2007|
|Also published as||US20090120205, WO2009064544A1|
|Publication number||11939680, 939680, US 8047233 B2, US 8047233B2, US-B2-8047233, US8047233 B2, US8047233B2|
|Inventors||Dan J. Clingman|
|Original Assignee||The Boeing Company|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (10), Non-Patent Citations (5), Referenced by (6), Classifications (10), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present invention is directed to apparatuses and methods for affecting fluid flow adjacent to a surface, and especially to apparatuses and methods for generating vortexes in fluid flow adjacent to a surface.
Vortex generating elements may be employed with aircraft, ships or ground vehicles to reattach separated fluid flow across exterior surfaces. Reattaching fluid flow across exterior surfaces may improve control characteristics, decrease transonic drag and generally fine tune vehicle performance in a specific operating regime. Use of vortex generating units may be referred to as active flow control. Active flow control may advantageously deploy vortex generating elements in a fluid stream adjacent to a surface, such as in the boundary layer of the fluid flow, at a locus upstream of the area of detached fluid flow. Vortex generating elements may be deployed only during certain evolutions such as, by way of example and not by way of limitation, during a steep climb, landing, take-off or transonic operation of an aircraft. Vortex generating elements may be deployed intermittently at a frequency that advantageously affects downstream attached fluid flow.
There is a need for precise and rapid control of deployment of vortex generating elements to permit accurately effecting active flow control for a vehicle.
An apparatus for generating vortexes in fluid flow generally adjacent to a surface includes: (a) at least one vortex generating element; and (b) a piezoelectric motor element coupled with the at least one vortex generating element. The piezoelectric motor element responds to a varying voltage signal to move the at least one vortex generating element between a first position extending into the fluid flow an operating distance from the surface and a second position generally flush with the surface.
A method for generating vortexes in fluid flow generally adjacent to a surface includes: (a) In no particular order: (1) providing at least one vortex generating element; and (2) providing a piezoelectric motor element coupled with the at least one vortex generating element. (b) Operating the piezoelectric motor element responsive to a varying voltage signal to move the at least one vortex generating element between a first position extending into the fluid flow an operating distance from the surface and a second position generally flush with the surface.
Therefore, it is a feature of the present disclosure to provide precise and rapid control of deployment of vortex generating elements to permit accurately effecting active flow control for a vehicle.
Further features of the present disclosure will be apparent from the following specification and claims when considered in connection with the accompanying drawings, in which like elements are labeled using like reference numerals in the various figures, illustrating embodiments of the disclosure.
Fluid flow in
Each of first vortex generating elements 12 n may be angularly displaced to the left in
Fluid flow past second vortex generating element 14 1 may thereby be oriented substantially about flow axis 18. Fluid flow past second vortex generating element 14 2 may be oriented substantially about flow axis 20. Fluid flow past second vortex generating element 14 3 may be oriented substantially about flow axis 22. Fluid flow past second vortex generating element 14 m may be oriented substantially about flow axis 24.
Each of first vortex generating elements 14 m may be angularly displaced to the right in
Vortex generating apparatus 10 may employ only first vortex generating elements 12 n, may employ only vortex generating elements 14 m, may employ all of vortex generating elements 12 n, 14 m or may employ another combination of vortex generating elements 12 n, 14 m.
Motor element 40 may be configured as a piezoelectric motor element having a first tilt plate 42 movably coupled with a base member 46 at a first base connection locus 50, and having a second tilt plate 44 movably coupled at a second base connection locus 52 with base member 46. A buckled beam bias member 48 may be coupled with tilt plate 42 at a first bias locus 54 displaced from base connection locus 50. Buckled beam bias member 48 may also be coupled with tilt plate 44 at a second bias locus 56 displaced from base connection locus 52.
Motor element 40 may further include a piezoelectric element 60. Piezoelectric element 60 may be a bimorph piezoelectric element. A bimorph piezoelectric element may be a piezoelectric element having two active layers that produce a displacement of the element causing one active layer to extend and the other active layer to contract in response to an electrical signal applied to the element.
Piezoelectric element 60 may rest at a first position (indicated as piezoelectric element 60 in solid line format in
Piezoelectric element 60 may rest at a second position indicated as piezoelectric element 60′ in dotted line format in
The first position of piezoelectric element 60 may be referred to as a first equilibrium position, and the second position of piezoelectric element 60′ may be referred to as a second equilibrium position.
Biasing piezoelectric element 60 using bias element 48 in cooperation with tilt plates 42, 44 and base member 46 permits motor element 40 to present enhanced displacement of piezoelectric element 60 in response to voltage signals applied at termini 62, 64. Operation of motor element 40 may be described in detail in co-pending U.S. patent application Ser. No. 11/584,305 filed Oct. 20, 2006 for “ENHANCED DISPLACEMENT PIEZOELECTRIC MOTOR” and assigned to the assignee of the present application. Directly coupling carrier element 30 with piezoelectric element 60 without any intervening transmission element permits rapid deployment of vortex generating elements 12 n, 14 m controlled by voltage signals applied to piezoelectric element 60. Eliminating a transmission element also may result in reduced cost and smaller size for vortex generating apparatus 10 as compared with other vortex generating apparatuses having similar operating characteristics.
A rectangular vortex generating element 70 is similar in construction to vortex generating elements 12 n, 14 m (
Rod-shaped vortex generating element 74 may have any of several cross-section shapes. Cross-section of rod-shaped element 74 may be a substantially circular shape 80; an oval shape (not shown); a polygonal such as, by way of illustration and not by way of limitation, an octagonal shape 82, a “cross” shape 84, a pentagonal shape 86 or a triangular shape 88; or another shape.
Method 100 may continue with operating the piezoelectric motor element responsive to a varying voltage signal to move the at least one vortex generating element between a first position extending into the fluid flow an operating distance from the surface and a second position generally flush with the surface, as indicated by a block 108. Method 100 may terminate at an END locus 110.
It is to be understood that, while the detailed drawings and specific examples given describe preferred embodiments of the disclosure, they are for the purpose of illustration only, that the apparatus and method of the disclosure are not limited to the precise details and conditions disclosed and that various changes may be made therein without departing from the spirit of the disclosure which is defined by the following claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US5755408||Apr 3, 1995||May 26, 1998||Schmidt; Robert N.||Fluid flow control devices|
|US5785282||Aug 7, 1996||Jul 28, 1998||Sikorsky Aircraft Corporation||Half-plow vortex generators for rotorcraft blades for reducing blade-vortex interaction noise|
|US6105904||Mar 30, 1998||Aug 22, 2000||Orbital Research Inc.||Deployable flow control device|
|US6685143||Jan 3, 2003||Feb 3, 2004||Orbital Research Inc.||Aircraft and missile forebody flow control device and method of controlling flow|
|US20040129838||Jan 3, 2003||Jul 8, 2004||Lisy Frederick J.||Flow control device and method of controlling flow|
|US20070018056 *||Jun 30, 2006||Jan 25, 2007||Bell Helicopter Textron Inc.||Retractable vortex generator|
|US20080092354 *||Oct 20, 2006||Apr 24, 2008||The Boeing Company||Piezoelectric bimorph beam manufacturing method|
|US20080100179 *||Oct 20, 2006||May 1, 2008||The Boeing Company||Enhanced displacement piezoelectric motor|
|JPH0516892A||Title not available|
|WO2007005687A1||Jun 30, 2006||Jan 11, 2007||Bell Helicopter Textron Inc.||Retractable vortex generator|
|1||Barrett, Ron & Farokhi, Saeed; "Subsonic Aerodynamics and Performance of a Smart Vortex Generator System"; Journal of Aircraft; vol. 33, No. 2, Mar.-Apr. 1996; pp. 393-398.|
|2||Clingman, Dan J.; "Development of an Aerodynamic Synthetic Jet Actuator Based on a Piezoelectric Buckled Beam"; Master's of Science in Aerospace Engineering Degree Thesis; University of Maryland; Feb. 2006.|
|3||Lin, J.C.; "AIAA 99/3404 Control of Turbulent Boundary-Layer Separation Using Micro-Vortex Generators"; 30th AIAA Fluid Dynamics Conference; Jun. 28-Jul. 1, 1999; Norfolk, VA.|
|4||Osborn, Russell F.; Kota, Sridhar; Hetrick, Joel A.; Geister, Donald E.; Tilmann, Carl P. & Joo, Jinyong; "Active Flow Control Using High-Frequency Compliant Structures"; Journal of Aircraft; vol. 41, No. 3, May-Jun. 2004; pp. 603-609.|
|5||PCT International Search Report; PCT Application US2008/078330; filed Sep 30, 2008; Report Date Mar. 9, 2009.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8348200 *||Dec 23, 2009||Jan 8, 2013||Lockheed Martin Corporation||Synthetic jet actuator system and related methods|
|US9267491||Jul 2, 2013||Feb 23, 2016||General Electric Company||Wind turbine rotor blade having a spoiler|
|US9309903||Sep 30, 2013||Apr 12, 2016||The Boeing Company||Vortex generators|
|US20110147476 *||Jun 23, 2011||Lockheed Martin Corporation||Synthetic Jet Actuator System and Related Methods|
|US20110223022 *||Sep 15, 2011||General Electric Company||Actuatable surface features for wind turbine rotor blades|
|EP2853486A1||Sep 23, 2014||Apr 1, 2015||The Boeing Company||Vortex generators|
|U.S. Classification||137/809, 244/99.8, 244/200.1, 244/204.1, 244/199.1|
|Cooperative Classification||Y10T137/2093, B64C23/06, Y02T50/162|
|Nov 14, 2007||AS||Assignment|
Owner name: BOEING COMPANY A CORPORATION OF DELAWARE, ILLINOIS
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CLINGMAN, DAN J.;REEL/FRAME:020108/0790
Effective date: 20071105
|May 1, 2015||FPAY||Fee payment|
Year of fee payment: 4